1) a sealed container for magnetic tape or for photographic film (cassette)
2) not sealed (unsealed)
having been closed
shut, out of service
completely airtight
airtight
(of materials) not allowing water etc to pass through; (of a person) not moved or influenced (by something)
unable to be penetrated
without movement or sound; not having bubbles; (of an action, situation) continuing as in the past; a quiet and calm atmosphere
calm, motionless, quiet